The invention relates to a disk-shaped propellant module for a propellant charge, which can be composed of several such modules.
An increase in the efficiency of large-caliber tank cannons, as a rule, requires an increase in the charge density of the propellant powder. However, a homogeneous ignition of the complete charge becomes more and more problematic with an increase in the charge density because the clearances provided in the charge for the propagation of flames or hot plasmas are too small. A non-homogeneous ignition on the other hand can lead to the formation of asymmetrical pressure waves in the powder chamber, which can destroy the weapon.
A ring-shaped tablet for gas generators is disclosed in German published patent application number DE 39 23 046 A1 and is used in particular for airbag generators. In order to increase the optimum conversion speed, the respective tablet has a central axial ignition channel, from which radial ignition channels, arranged on the top and underside of the tablet, extend toward the tablet edge.
It is the object of the present invention to provide a propellant module of the aforementioned type, which ensures a uniform and symmetrical ignition of the propellant charge of a cartridge with increased charge density ( greater than 1.2 g/cm3).
The above object generally is achieved according to the invention by a disk-shaped propellant module for a propellant charge composed of several such modules, wherein the propellant module has at least three axially extending ignition channels that are uniformly distributed along a circle, and at least three radially extending ignition channels that extend from the inside or interior of the propellant module to the outer edge surface of the module, with the center of the circle on which the axial ignition channels are positioned is located on the central axis of the propellant module, and with each of the radially extending ignition channels intersecting with at least one of the axially extending ignition channels. Additional and particularly advantageous embodiments of the invention are disclosed in the dependent claims.
The essential idea behind the invention is to provide the propellant module with at least three, preferably six, axial ignition channels that are distributed uniformly along a circle, as well as at least three, preferably also six, radial ignition channels that extend from the interior, e.g., the center, of the propellant module to its outer surface. Each of the radial ignition channels in this case intersects at least one of the axial ignition channels. The central axis of the propellant module preferably forms the center of the circle on which the axial ignition channels are positioned.
In order to obtain a through ignition of the complete propellant charge, the individual propellant modules should be stacked inside the respective cartridge in such a way that their axial ignition channels together form one continuous ignition channel. The radial ignition channels ensure a better propagation of the flames or plasmas (in case of a plasma ignition) over the complete powder chamber. In addition, the radial ignition channels if possible should represent predetermined breakage points for the propellant powder disks. These predetermined breakage points allow an uninterrupted passage of the propellant charge in the area of transition from powder chamber to weapon tube since the radial ignition channels make it possible to achieve a defined structure of the respective propellant powder fragments.
It has proven advantageous if the separate propellant modules have a grooved chamfered surface, thus leaving a small clearance space between neighboring modules of the finished propellant for the lateral propagation of the flames over the complete powder chamber.
The use of multi-perforated propellant powder disks has proven useful to increase the progressiveness of the combustion, wherein the number of perforations should be between approximately 1000 and approximately 4000, depending on the desired progressiveness or wall thickness of the propellant module. The perforations can be inserted during the propellant powder extrusion or in the form of bores in a CNC-machine.
Further details and advantages of the invention follow from the exemplary embodiments below, which are explained with the aid of Figures.